This group portrait, taken in 1919, is of Sir Victor Goddard’s Royal Air Force squadron, and seems to feature the face of a mechanic who died two days earlier.

This group portrait of Goddard’s squadron, which had served in World War I at the HMS Daedalus training facility, is said to feature the ghostly face of Freddy Jackson, a mechanic who had been accidentally killed by an aeroplane propeller two days earlier. His face is said to be visible behind the airman in the top row, fourth from the left.

The photo was allegedly taken on the day of Jackson’s funeral.

The photo on the right was said to show the spirit of a deceased terrier reuniting with his canine best friend.

This picture of the supposed ghost of Abraham Lincoln with his widow, Mary Lincoln, was taken circa 1870. It is considered one of the first examples of spirit photography.

William Mumler was originally an engraver in Boston who treated photography as a side-hobby. After developing a self-portrait and discovering a surprise “girl made of light” in the final print, he became one of the first spirit photographers – someone whose principal goal is to capture ghosts and spirits in photographs. The title earned him both acclaim and scorn from the spiritualist community. Though many accused him of fraud, no one was able to debunk his methods.

Paranormal investigators sought to expose Hope as a fraud in 1922, but his believers never doubted him.

Hope was later exposed as a fraud in February 1922; paranormal investigator Harry Price went so far as to write in a report that: “William Hope has been found guilty of deliberately substituting his own [photographic] plates for those of a sitter… It implies that the medium brings to the sitting a duplicate slide and faked plates for fraudulent purposes.”

In other words, Hope used multiple exposure techniques to add ghostly spirits to photos.

Hope’s followers and fanbase remained loyal and even claimed to spot the controversial photographer’s ghost in photos after his death.

Originally taken in 1936 by Captain Hubert C. Provand, this photo allegedly shows a ghost that haunts Raynham Hall in Norfolk, England.

According to legend, the identity of the ghost in the photograph – the “Brown Lady of Raynham Hall” – is none other than Lady Dorothy Walpole, the sister of the first Prime Minister of Great Britain, Robert Walpole.

According to lore, Walpole – the second wife of Charles Townshend – had an affair with Lord Wharton. When Townshend found out he locked her up in Raynham Hall, where she stayed until her death in 1726.

This photo, taken in 1963, is of a supposed ghost named the “Specter of Newby Church.”

When Reverend K.F. Lord took this photo in 1963 inside the Newby Church in North Yorkshire, England, it was met with scepticism: many believed the apparition was merely the result of a well-done double exposure.

Lord maintained that the ghost in the photo wasn’t doctored.

Richard Boursnell, a spirit medium and photographer, captured this photo of spiritualist William Thomas Stead and a purported phantom who was identified as Piet Botha, a Boer commandant killed in the South African War.

A man named F. C. Barnes visited Boursnell in 1908 and attempted to expose the photographer as a fraud, claiming that he recognised the “phantom” in the photo as an image Boursnell had taken from a book of the late-Empress Elisabeth of Austria.